276 SERTULAIIIID.E. 



NIGELLASTRUM THUJA, OJcen, Lekrb. Nat. 93. 



THUIARIA THUIA, Flem. Brit. An. 54.3; Johnst. Br. Z. 83, pi. xrii. & xviii. 



figs. 1, 2. 

 BISERIARIA THUIA, Bluinv. Actinol. 482, pi. Ixxxi. fig. 3. 



Plate LIX. 



STEM filiform, rigid, zigzag (the spaces between the 

 angles very short) , ammlated towards the base, and 

 obliquely jointed for some way above it, black or dark 

 horn-colour and glossy, clothed with branches towards 

 the top, but in the adult state denuded of them through 

 the greater portion of its length; branches alternate, 

 somewhat spirally arranged (four forming a whorl) Jointed 

 to small projections (which remain after they have fallen, 

 and give a knotted appearance to the stem) , divided and 

 subdivided dichotomously ; branchlets rounded and taper- 

 ing towards the extremity ; HYDROTHEOE subalternate, 

 smooth, approximate, broadly ovate below, tapering 

 upwards, the aperture transversely oblong, somewhat 

 arched above ; GONOTHEC^E produced at the base of the 

 calycles, subpedicellate, pear-shaped, smooth, with a 

 circular, slightly margiuated and operculate aperture. 



THE fishermen's name for this species, " the Bottle-brush/ 5 

 which has been preserved by Ellis, gives an admirable idea 

 of its general appearance. The stems, which sometimes 

 attain the height of a foot, are bare for a great portion of 

 their length, the lower branches dying off as growth pro- 

 ceeds, while the upper, which remain attached, form a 

 cylindrical brush, of varying size, at the top ; they are 

 strongly annulated at the base, and spring from a dark, 

 spreading crust, concentrically wrinkled. Both Pallas and 

 Johnston describe the stem as being destitute of calycles 

 and joints ; but this is far from being the case. The lower 

 portion of it is divided into segments by strongly marked 

 oblique joints, which, however, do not extend upwards, or 

 at least only occur occasionally and without regularity ; 



